The merger of Kraft and Heinz was orchestrated by 3G Capital, which is helmed by Brazilian billionaire Jorge Lemann, and Warren Buffett's Berkshire Hathaway.

Ackman himself is an investor in 3G's funds.

The private-equity firm has wasted little time in shaking up the upper ranks of the newly-combined company, and has a reputation for savage cost-cutting.

Lemann, a Swiss-Brazilian, has gone from journalist to national tennis champion to banker and now billionaire investor. Buffett likes to call him, "Georgie Paolo."

"Money is simply a way of measuring if the business is going well or not, but money in and of itself doesn't fascinate me," Lemann said in January 2008, according to an interview published in HSM Management magazine.

Lemann was born in Rio de Janeiro in 1939. His father was a Swiss businessman who immigrated to Brazil in the 1920s.

He left Brazil to attend Harvard, earning his bachelor's degree in economics in 1961. Lemann still has a great relationship with Harvard, helping Brazilian students study there and setting up scholarships.

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After Harvard, Lemann's life was a mixed bag. He trained at Credit Suisse for a while and worked as a journalist at Brazil's third-oldest paper, Jornal do Brasil.

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He was also a tennis champion. Lemann was Brazil's national champion five times. He represented Brazil and Switzerland (he has dual citizenship) in the Davis Cup. He also made it to Wimbledon.

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In 1971 he bought a brokerage called Garantía.

Lemann wanted to turn it into Brazil's Goldman Sachs by adopting the American firm's partnership model. A few years later his current partners, Carlos Alberto Sicupira and Marcel Herrmann Telles, joined him (they are also now billionaires, by the way).

The trio, known as the "Three Musketeers" would go on to buy Lojas Americanas SA, a now huge chain of retail stores in Brazil in, 1982.

In 1989, Lemann and company acquired the beer company Cia Cervejaria Brahma, foreshadowing things to come. In 1993, he and his partners created the buyout firm GP Investimentos and started buying and selling companies.

Check out a commercial Megan Fox made for Brahma below:

Along the way, he built Garantía into a powerhouse, eventually selling it for $675 million in 1998.

That takes us to the $10 billion Heinz-Kraft deal. All signs point to more deals from Lemann. People say he changed the way business is done in Brazil.

"Jorge Paulo created a whole management culture in Brazil that is extraordinary," [former Brazilian billionaire Eike] Batista told Bloomberg Markets magazine in an interview in 2012. "He motivated employees by letting them share the profits -- aggressive, but that leads to results."